Embed Size (px)
Citation preview
Asteroseismology as an exoplanet toolTASC2 & KASC9 Workshop – July 2016
Vincent Van Eylen
Oort FellowLeiden University
Solar system
Solar system
Solar system
Giant exoplanet
Solar system
Giant exoplanet
Multiple planets ?
Solar system
Giant exoplanet
Multiple planets ? ?
How to observe obliquities?
Rossiter-McLaughlin effect
Large planets
Asteroseismology
Accurate mass, radius, age, ...
... and stellar inclination!Independent of planet
?
How to observe obliquities?
Rossiter-McLaughlin effect
Large planets
Asteroseismology
Accurate mass, radius, age, ...
... and stellar inclination!Independent of planet
?
Rotational splitting provides info on stellar rotation and inclination
1920 1940 1960 1980 2000 2020Frequency [µHz]
0.0
0.1
0.2
0.3
0.4
0.5
Power
[ppm
2]
i=45 ◦
i=82.5 ◦ (best fit)
l=1l=2
l=0m= -1 0 1
Van Eylen et al. 2014
Rotational splitting provides info on stellar rotation and inclination
1920 1940 1960 1980 2000 2020Frequency [µHz]
0.0
0.1
0.2
0.3
0.4
0.5
Power
[ppm
2]
i=45 ◦
i=82.5 ◦ (best fit)
l=1l=2
l=0m= -1 0 1
Van Eylen et al. 2014
Rotational splitting provides info on stellar rotation and inclination
1920 1940 1960 1980 2000 2020Frequency [µHz]
0.0
0.1
0.2
0.3
0.4
0.5Pow
er[ppm
2]
i=45 ◦
i=82.5 ◦ (best fit)
l=1l=2
l=0m= -1 0 1
Van Eylen et al. 2014
1 Obliquity of multi-planet systems?
Values from: Sanchis-Ojeda et al. 2012, Hirano et al. 2012, Albrecht et al. 2013,Chaplin et al. 2013, Huber et al. 2013, Van Eylen et al. 2014, Benomar et al. 2014
Ensemble study: Campante et al. 2016
1 Obliquity of multi-planet systems?
Values from: Sanchis-Ojeda et al. 2012, Hirano et al. 2012, Albrecht et al. 2013,Chaplin et al. 2013, Huber et al. 2013, Van Eylen et al. 2014, Benomar et al. 2014
Ensemble study: Campante et al. 2016
1 Obliquity of multi-planet systems: low
2 Obliquity of single-planet systems: a wide range
5000 6000 7000 8000Teff [K]
0
30
60
90
120
150
180
proj
. obl
iqui
ty [d
eg]
Albrecht et al. 2012
1 Obliquity of multi-planet systems: low
2 Obliquity of single-planet systems: a wide range
5000 6000 7000 8000Teff [K]
0
30
60
90
120
150
180
pro
j. o
bliq
uity [deg]
Albrecht et al. 2012Tides?
1 Obliquity of multi-planet systems: low
2 Obliquity of single-planet systems: a wide range
5000 6000 7000 8000Teff [K]
0
30
60
90
120
150
180
pro
j. o
bliq
uity [deg]
0 1 2 3 4 5 6 7 8 9
Time [d]
0.92
0.94
0.96
0.98
1.00
Norm
aliz
ed f
lux
t1 = 2.112 Porb/2 t2 = 6.566
2.0 2.1 2.2 2.3
Time [d]
0.92
0.94
0.96
0.98
1.00
Norm
aliz
ed f
lux
6.4 6.5 6.6 6.7
Time [d]
0.92
0.94
0.96
0.98
1.00
Obliquity Binary star eccentricity
Winn et al. 2010, Albrecht et al. 2012 Van Eylen, Winn & Albrecht 2016
1 Obliquity of multi-planet systems: low
2 Obliquity of single-planet systems: a wide range
5000 6000 7000 8000Teff [K]
0
30
60
90
120
150
180
pro
j. o
bliq
uity [deg]
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8Log(10) P
0.0
0.2
0.4
0.6
0.8
1.0
Pe
rce
nta
ge
of
ecc
en
tric
orb
its
pe
r b
in
Obliquity Binary star eccentricity
Winn et al. 2010, Albrecht et al. 2012 Van Eylen, Winn & Albrecht 2016
1 Obliquity of multi-planet systems: low
2 Obliquity of single-planet systems: a wide range
5000 6000 7000 8000Teff [K]
0
30
60
90
120
150
180
pro
j. o
bliq
uity [deg]
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8Log(10) P
0.0
0.2
0.4
0.6
0.8
1.0
Perc
enta
ge o
f ecc
entr
ic o
rbit
s per
bin Cool-cool Hot-cool Hot-hot
Obliquity Binary star eccentricity
Winn et al. 2010, Albrecht et al. 2012 Van Eylen, Winn & Albrecht 2016
Solar system
Giant exoplanet
?
Solar system
Giant exoplanet
Solar system
Giant exoplanet
?
10-2 10-1 100 101 102 103 104
Mass [M⊕]
0.0
0.2
0.4
0.6
0.8
1.0Ecc
entr
icit
y
Solar system
Eccentricities from RV detections from exoplanets.org (27 April ’15).
10-2 10-1 100 101 102 103 104
Mass [M⊕]
0.0
0.2
0.4
0.6
0.8
1.0Ecc
entr
icit
y
Solar systemRV planets
Eccentricities from RV detections from exoplanets.org (27 April ’15).
10-2 10-1 100 101 102 103 104
Mass [M⊕]
0.0
0.2
0.4
0.6
0.8
1.0Ecc
entr
icit
y
Solar systemRV planets
Eccentricities from RV detections from exoplanets.org (27 April ’15).
How to observe eccentricity?
1
2
Time
Radial Velocity
[m/s]
21
+
-
How to observe eccentricity?
Time
Radial Velocity
[m/s]
21
+
-1
2
Small planets: no RV possible. Eccentricity? Transit durations!
Transit duration ∝ ρ?(1+e sinω)3
(1−e2)3/2
⇒ measure the stellar density ρ? (asteroseismology)⇒ marginalize over unknown orientation ω
Small planets: no RV possible. Eccentricity? Transit durations!
Transit duration ∝ ρ?(1+e sinω)3
(1−e2)3/2
⇒ measure the stellar density ρ? (asteroseismology)⇒ marginalize over unknown orientation ω
?
10-2 10-1 100 101 102 103 104
Mass [M⊕]
0.0
0.2
0.4
0.6
0.8
1.0
Ecc
entr
icit
y
Solar systemRV planets
10-2 10-1 100 101 102 103 104
Mass [M⊕]
0.0
0.2
0.4
0.6
0.8
1.0
Ecc
entr
icit
y
Solar systemRV planetsVan Eylen & Albrecht 2015
Asteroseismic ρ? from Silva Aguirre et al. 2015 and Lundkvist et al. 2015
10-2 10-1 100 101 102 103 104
Mass [M⊕]
0.0
0.2
0.4
0.6
0.8
1.0
Ecc
entr
icit
y
Solar systemRV planetsVan Eylen & Albrecht 2015
Asteroseismic ρ? from Silva Aguirre et al. 2015 and Lundkvist et al. 2015
10-2 10-1 100 101 102 103 104
Mass [M⊕]
0.0
0.2
0.4
0.6
0.8
1.0
Ecc
entr
icit
y
Solar systemRV planetsMulti-planet systems Van Eylen & Albrecht 2015Single-planet systems Van Eylen et al. (in prep.)
Asteroseismic ρ? from Silva Aguirre et al. 2015 and Lundkvist et al. 2015
10-2 10-1 100 101 102 103 104
Mass [M⊕]
0.0
0.2
0.4
0.6
0.8
1.0
Ecc
entr
icit
y
Solar systemRV planetsMulti-planet systems Van Eylen & Albrecht 2015Single-planet systems Van Eylen et al. (in prep.)
Asteroseismic ρ? from Silva Aguirre et al. 2015 and Lundkvist et al. 2015
“Two types” of planetary systems?1 flat, circular systems
2 systems with higher mutual inclinations and eccentricities
Consistent with simulations by e.g. Dawson, Lee & Chiang 2016:
graviational scattering increase inclination/eccentricity
mergers dampen, depending on gas density
“Two types” of planetary systems?1 flat, circular systems
2 systems with higher mutual inclinations and eccentricities
Consistent with simulations by e.g. Dawson, Lee & Chiang 2016:
graviational scattering increase inclination/eccentricity
mergers dampen, depending on gas density
Asteroseismology of planet host starswith K2? TESS?
Cadence and/or amplitude issues ⇒ Giants!
Giants orbiting (sub)giants
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5logg [cgs]
10-3
10-2
10-1
100
101
a [
AU
]
??
Transit Detection
RV Detection
There are very few short-period (giant) planets orbiting evolved stars.e.g. Bowler et al. 2010, Johnson et al. 2010, Reffert et al. 2015
Why is this?
Explanation 1:The observed evolved stars have a systematically higher mass, thismake the lifetime of the protoplanetary disk shorter.e.g. Burkert & Ida 2007, Kretke et al. 2009, Currie 2009
Explanation 2:As stars evolve, short-period planets are destroyed.e.g. Rasio et al. 1996, Villaver & Livio 2009, Schlaufman & Winn 2013
To make progress, new short-period planets are needed.
There are very few short-period (giant) planets orbiting evolved stars.e.g. Bowler et al. 2010, Johnson et al. 2010, Reffert et al. 2015
Why is this?
Explanation 1:The observed evolved stars have a systematically higher mass, thismake the lifetime of the protoplanetary disk shorter.e.g. Burkert & Ida 2007, Kretke et al. 2009, Currie 2009
Explanation 2:As stars evolve, short-period planets are destroyed.e.g. Rasio et al. 1996, Villaver & Livio 2009, Schlaufman & Winn 2013
To make progress, new short-period planets are needed.
There are very few short-period (giant) planets orbiting evolved stars.e.g. Bowler et al. 2010, Johnson et al. 2010, Reffert et al. 2015
Why is this?
Explanation 1:The observed evolved stars have a systematically higher mass, thismake the lifetime of the protoplanetary disk shorter.e.g. Burkert & Ida 2007, Kretke et al. 2009, Currie 2009
Explanation 2:As stars evolve, short-period planets are destroyed.e.g. Rasio et al. 1996, Villaver & Livio 2009, Schlaufman & Winn 2013
To make progress, new short-period planets are needed.
K2-39
Sun
K2-39b
K2-39 K2-39bSun Mercury
−0.154 0.154
0.9995
1.0000
1.0005
rela
tive
flu
x
−0.154 0.154
−0.0004−0.0002
0.00000.00020.0004
O −
C
−15 −10 −5 0 5 10 15time (hr)
−0.05 1.05
−40
−20
0
20
40
rad
ial ve
locity (
m s
−1)
HARPSFIESPFS
0.0 0.2 0.4 0.6 0.8 1.0orbital phase
−30−20−10
0102030
O −
C (
m s
−1)
↪→ R = 8.2+1.1−1.1 R⊕ ↪→ M = 50.3+9.7
−9.4 M⊕
Van Eylen et al. 2016b, Van Eylen et al. 2016c
0 1 2 3 4 5 6 7 8R [R¯]
0.1
0.2
0.3
0.4
0.5a [
AU
]
K2-39b
Kep-91b
Kep-432b
Kep-391b
Kep-391c
Kep-56b
Kep-56c
HD 102956b
Van Eylen et al. 2016c
See also poster S13.81 by Grunblatt et al.!
Conclusions
Asteroseismology as/is an exoplanet tool!
Kepler era: progress on dynamics of exoplanet systemsObliquity measurements (for multi-planet systems)
Eccentricity measurements of planet orbits
Future: asteroseismology of giant planet host stars
Planet occurrence? (Re)inflation of hot Jupiters?
Data ideally suited for progress
